1. Field of the Invention
The invention disclosed broadly relates to the field of electronic commerce and more particularly to a system and related tools for the secure delivery and rights management of digital assets, such as print media, films, games, and music over global communications networks such as the Internet and the World Wide Web.
2. Description of the Related Art
The use of global distribution systems such as the Internet for distribution of digital assets such as music, film, computer programs, pictures, games and other content continues to grow. At the same time owners and publishers of valuable digital content have been slow to embrace the use of the Internet for distribution of digital assets for several reasons. One reason is that owners are afraid of unauthorized copying or pirating of digital content. The electronic delivery of digital content removes several barriers to pirating. One barrier that is removed with electronic distribution is the requirement of the tangible recordable medium itself (e.g., diskettes or CD ROMs). It costs money to copy digital content on to tangible media, albeit, in many cases less than a dollar for a blank tape or recordable CD. However, in the case of electronic distribution, the tangible medium is no longer needed. The cost of the tangible medium is not a factor because content is distributed electronically. A second barrier, is the format of the content itself i.e. is the content stored in an analog format versus a digital format. Content stored in an analog format, for example, a printed picture, when reproduced by photocopying, the copy is of lesser quality than the original. Each subsequent copy of a copy, sometimes called a generation, is of less quality than the original. This degradation in quality is not present when a picture is stored digitally. Each copy, and every generation of copies can be as clear and crisp as the original. The aggregate effect of perfect digital copies combined with the very low cost to distribute content electronically and to distribute content widely over the Internet makes it relatively easy to pirate and distribute unauthorized copies. With a couple of keystrokes, a pirate can send hundreds or even of thousands of perfect copies of digital content over the Internet. Therefore a need exists to ensure the protection and security of digital assets distributed electronically.
Providers of digital content desire to establish a secure, global distribution system for digital content that protects the rights of content owners. The problems with establishing a digital content distribution system includes developing systems for digital content electronic distribution, rights management, and asset protection. Digital content that is distributed electronically includes content such as print media, films, games, programs, television, multimedia, and music.
The deployment of an electronic distribution system provides the digital content providers the ability to achieve fast settlement of payment through immediate sales reporting and electronic reconciliation as well as gain secondary sources of revenue through redistribution of content. Since the electronic digital content distribution system is not affected by physical inventory outages or returns, the digital content providers and retailers may realize reduced costs and improved margins. Digital content providers could facilitate new, or augment existing, distribution channels for better timed-release of inventory. The transactional data from the electronic distribution system could be used to obtain information regarding consumer buying patterns as well as to provide immediate feedback on electronic marketing programs and promotions. In order to meet these goals, a need exists for digital content providers to use an electronic distribution model to make digital content available to a wide range of users and businesses while ensuring protection and metering of digital assets.
Other commercially available electronic distribution systems for digital content, such as real audio, A2B from ATandT, Liquid Audio Pro from Liquid Audio Pro Corp., City Music Network from Audio Soft and others offer transmission of digital data over secured and unsecured electronic networks. The use of secured electronic networks greatly reduces the requirement of digital content providers of distributing digital to a wide audience. The use of unsecured networks such as the Internet and Web allows the digital content to arrive to an end-user securely such as through the use of encryption. However, once the encrypted digital content is de-encrypted on the end-user""s machine, the digital content is readily available to the end-user for unauthorized re-distribution. Therefore a need exists for a secure digital content electronic distribution system that provides protection of digital assets and ensures that the Content Provider(s)"" rights are protected even after the digital content is delivered to consumers and businesses. A need thus exists for rights management to allow for secure delivery, licensing authorization, and control of the usage of digital assets.
Another reason owners of digital content have been slow to embrace electronic distribution is their desire to maintain and foster existing channels of distribution. Most content owners sell through retailers. In the music market these U.S. retailers include Tower Records, Peaches, Blockbuster, Circuit City and others. Many of these retailers have Web sites that allow Internet users to makes selections over the Internet and have selections mailed to the end-user. Example music Web sites include @tower, Music Boulevard and Columbia House. The use of electronic distribution can remove the ability of the retail stores from differentiating themselves from each other and differentiate themselves from the content owners, especially on the Web. Therefore a need exists to provide retailers of electronic content such as pictures, games, music, programs and videos a way to differentiate themselves from each other and the content owners when selling music through electronic distribution.
Content owners prepare their digital content for electronic distribution through distribution sites such as electronic stores. Electronic stores on the Internet, or through other online services, want to differentiate themselves from each other by their product offerings and product promotions. A traditional store, i.e.xe2x80x94the non-electronic, non-online analogs to electronic storesxe2x80x94use product promotions, product sales, product samples, liberal return policies and other promotional programs to differentiate themselves from their competitors. However, in the online world where the content providers impose usage conditions on the digital content, the ability of electronic stores to differentiate themselves may be severely limited. Moreover, even if the usage conditions can be changed, electronic stores are faced with the difficult task of processing the metadata associated with the digital content from the content providers to promote and sell products electronically. Electronic stores need to manage several requirements when processing the metadata. First, the electronic store is required to receive the metadata associated with the digital content from the content providers. Many times, parts of this metadata may be sent encrypted, so the content provider must create a mechanism to decrypt the encrypted content. Second, the electronic store may wish to preview metadata from the content provider either before the content is received from the content provider or after the content is received by the electronic store, in order to assist with product marketing, product positioning and other promotional considerations for the content. Third, the electronic store is required to extract certain metadata used for promotional materials such as graphics and artist information. Often, this promotional material is used directly by the electronic store in its online promotions. Fourth, the electronic stores may wish to differentiate themselves from one another by modifying some of the permitted usage conditions to create different offerings of the digital content. Fifth, the electronic store may have to insert or alter certain address, such as URLs, in the metadata to direct payment reconciliation to an account reconciliation house automatically by the purchaser without the need to go through the electronic store for payment clearance. Sixth, the electronic store may need to create licenses for the permitted use of the copyrighted digital content that match usage conditions. For example, the license may grant the permission to make a limited number of copies of the digital content. A license is needed to reflect the terms and conditions of the permission granted.
In light of all these requirements, to process the metadata related to the digital content, many electronic stores write customized software programs to handle these requirements. The time, cost and testing needed to create these customized software programs can be large. Accordingly, a need exists to provide a solution to these requirements.
Still, another reason owners of digital content have been slow to embrace electronic distribution is the difficulty in preparing content for electronic distribution. Today, many providers of content have thousands or even tens of thousands of titles in their portfolio. In a music example, it is not unusual for a content owner to have a single master sound recording available on several different formats simultaneously (e.g. CD, tape and MiniDisc). In addition, a single format can have a master sound recording re-mastered or re-mixed for a specific distribution channel. As an example, the mixing for broadcast radio may be different than the mixing for a dance club sound track, which may be different than a generally available consumer CD. Inventorying and keeping track of these different mixes can be burdensome. Moreover, many owners of master recordings often times re-issue old recordings in various subsequent collections, such as xe2x80x9cThe Best Ofxe2x80x9d, or in compilations for musical sound tracks to movies and other collections or compilations. As more content is offered digitally, the need to re-mix and encode the content for electronic distribution grows. Many times providers need to use old recording formats as guides to select the correct master sound recordings and have these sound recordings reprocessed and encoded for release for electronic distribution. This may be especially true for content providers that wish to use their old formats to assist them in re-releasing the old sound recording for electronic distribution. Providers will look through databases to match up titles, artists and sound recordings to set the encoding parameters. This process of manually searching databases for recording portfolios is not without its shortcomings. One shortcoming is the need to have an operator manually search a database and set the processing parameters appropriately. Another shortcoming is the possibility of operator transcription error in selecting data from a database. Accordingly, a need exists to provide content providers a method to automatically retrieve associated data and master recordings for content such as audio.
Content owners prepare their digital content for electronic distribution through a process known as encoding. Encoding involves taking the content, digitizing it, if the content is presented in an analog format, and compressing it. The process of compressing allows the digital content to be transferred over networks and stored on recordable medium more efficiently because the amount of data transmitted or stored is reduced. However, compression is not without its shortcomings. Most compression involves the loss of some information, and is called lossy compression. Content providers must make decisions on what compression algorithm to use and the compression level required. For example, in music, the digital content or song may have very different characteristics depending on the genre of the music. The compression algorithm and compression level selected for one genre may not be the optimal choice for another genre of music. Content providers may find certain combinations of compression algorithms and compression levels work very well for one genre of music, say classical, but provide unsatisfactory results for another genre of music such as heavy metal. Moreover, audio engineers must often equalize the music, perform dynamic range adjustments and perform other preprocessing and processing settings to ensure the genre of music encoded produces the desired results. The requirement to always have to manually set these encoding parameters such as setting the equalization levels and the dynamic range settings for each digital content can be burdensome. Returning to the music example, a content provider for music with a collection covering a variety of musical genre would have to manually select for each song or set of songs to be encoded, the desired combination of encoding parameters. Accordingly, a need exists to overcome the need for manually selection of process parameters for encoding.
The process to compress content can require a large amount of dedicated computational resources, especially for larger content items such as full-length feature movies. Providers of compression algorithms offer various tradeoffs and advantages associated with their compression techniques. These tradeoffs include: the amount of time and computational resources needed to compress the content; the amount of compression achieved from the original content; the desired bit rate for playback; the performance quality of the compressed content; and other factors. Using an encoding program which take as input a multimedia file and generate an encoded output file with no interim indication of progress or status is a problem. Moreover, in many circumstances, other programs are used to call or to manage an encoding program with no interim indication of progress. This leaves the calling application with no way to gauge the amount of content that has been encoded as a percentage of the entire selection of designated to be encoded. In circumstances where the calling program is trying to schedule several different programs to run at once this can be a problem. Furthermore, this can be especially burdensome in cases where batches of content have been selected for encoding and the content provider wants to determine the progress of the encoding process. Accordingly, a need exists to overcome these problems.
Yet, still another reason digital content providers have been slow to adopt electronic distribution for their content is lack of standards for creating digital players on end-user devices for electronically delivered content. Content providers, electronic stores, or others in the electronic distribution chain may want to offer customized players on a variety of devices such as PCS, set-top boxes, hand-held devices and more. A set of tools that can handle the decryption of the digital content in a tamper resistant environment, that is, an environment to deter the unauthorized access to the content during playing by a third party is needed. Moreover, a set of tools is needed to enable an end user to manage of a local library of digital content without allowing the end user to have access to the content for uses other than what was purchased.
Further information on the background of protecting digital content can be found from the following three sources. xe2x80x9cMusic on the Internet and the Intellectual Property Protection Problemxe2x80x9d by Jack Lacy, James Snyder, David Maher, of ATandT Labs, Florham Park, N.J. available online URL http://www.a2bmusic.com/about/papers/musicipp.htm. Cryptographically protected container, called Digibox, in the article xe2x80x9cSecuring the Content, Not the Wire for Information Commercexe2x80x9d by Olin Sibert, David Bernstein and David Van Wie, InterTrust Technologies Corp. Sunnyvale, Calif. available online URL http://www.intertrust.com/architecture/stc.html. And xe2x80x9cCryptolope Container Technologyxe2x80x9d, an IBM White Paper, available online URL http:///cyptolope.ibm.com/white.htm.
It is an object of the present invention to remove the above-mentioned drawbacks and to provide a key management system for a digital content player. One embodiment of the present invention provides a method of managing keys used by a digital content player on a computer system. According to the method, digital content data encrypted with a first encrypting key is decrypted using a first decrypting key, and re-encrypted using a second encrypting key. A second decrypting key is encrypted using a third encrypting key to produce an encrypted second decrypting key. In one preferred method, an encrypted first decrypting key that was encrypted using a fourth encrypting key is received, and the encrypted first decrypting key is decrypted using a fourth decrypting key to reproduce the first decrypting key. In such embodiments, the first decrypting key can be used to decrypt data that has been encrypted with the first encrypting key, the second decrypting key can be used to decrypt data that has been encrypted with the second encrypting key, and so on. Further, in various embodiments, an encrypting key and its corresponding decrypting key can be symmetric keys (i.e., identical) or a key pair (e.g., a public key and its corresponding private key).
Another embodiment of the present invention provides a digital content player for use on a computer system. The content player includes a decrypter that decrypts digital content data, which was encrypted with a first encrypting key, using a first decrypting key so as to produce the content data. An encrypter re-encrypts the content data using a second encrypting key and encrypts a second decrypting key using a third encrypting key. In one preferred content player, a receiver receives an encrypted first decrypting key that was encrypted using a fourth encrypting key, and the decrypter decrypts the encrypted first decrypting key using a fourth decrypting key to reproduce the first decrypting key.